In the related art, there is a technology for specifying an upper limit of an vacant band in a network that connects devices. For example, there is a binary search technology of path load for specifying an upper limit of an vacant band in a network based on comparison of a transmission rate with a reception rate in magnitude.
For example, as the related art, there is a technology for estimating an available bandwidth of a channel by transmitting a test stream to a reception node, receiving the returned test stream, measuring quality information such as the round-trip time or a packet loss rate, and applying the quality information to a NW analysis model.
An example of the related art includes Japanese Laid-open Patent Publication No. 2008-278207.